EXPERIMENTAL MODEL OF HEPATIC TUMOR IN THE RAT. DESCRIPTION AND RESULTS OF INTRAHEPATIC IMPLANTATION TECHNIQUE

Abstract

In order to investigate new therapeutic strategies for hepa tocellular carcinoma (HCC), an animal model easily repro ducible of hepatic tumor is necessary. Several techniques of intrahepatic tumor implantation have been reported in the literature. Many of them have the disadvantage of high rate of artificial neoplastic extrahepatic dissemination, both peri toneal and systemic. These drawbacks interfere with the eva luation of treatment efficacy.

In this study we describe a modified technique of intrahe patic tumor implantation in the rat, previously reported by Yang in 1992, which is based on the insertion in the liver, after neoplastic tissue, of a piece of hemostatic sponge (Spongostan®) that permits to significantly reduce the rate of artificial neoplastic dissemination.

Nine ACI/T rats were used and Morris hepatoma 3924A was implanted in the right hepatic lobe. In all cases an intrahepatic tumor take was documented by MRI and by histological examination. No lung metastases were observed. In only one animal peritoneal and subcutaneous nodules were seen, likely due to a technique mistake. According to tumor growth curve it is possible to observe that, with this technique, a 1 cm tumor nodule is obtainable 10 days after the implantation, without extrahepatic metastases, easily detectable by imaging techniques such as MRI used in this study.

In conclusion this modified technique of intrahepatic tumor implantation permits to obtain an intrahepatic tumor ani mal model which is easily reproducible and suitable for the evaluation of efficacy of experimental therapies for HCC.